Apparatus for concentrating liquids.



P. KESTNER.

APPARATUS FOR OONGENTRATING LIQUIDS.

APPLICATION FILED JULY 20,1910.

Patented Dec. 26, 1911.

111111111 IIII/[IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII/ 9,5

PAUL KESTNER; or LILLE, FRANCE, ASSIGNOR ro KES'INER nvnrom'ron comrAnY;

OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

APPARATUS FOR CONCENTRATING- LIQUIDS.

Original application filed November 1, 1909. Serial No.

525,710 Divided and this application filed.- J'uly 20,-

1910. Serial No. 572,855.

To all whom it may concern:

Be itknown that 1, PAU KESTNER, a citizen of the Republic of France, and a resident of Lille, Department Nerd, France,

have invented certain Improvements in Ap paratus for Concentrating Liquids, (being a division of my application filed November 1, 1909, Serial No. 525,710,) of which the following is a specification.

My invention relates to apparatus for evaporating liquid or liquid bodies; and the object of my invention is to provide improved means for feeding such liquid or liquid bodies to the base of vertical tube evaporators in which concentration or evaporation 1S effected by the climbing of the liquid within elongated tubes externally heated that will insure an even and simul taneous feed of the liquid or liquid bodies thereto. I I

In modern types of evaporators, tlie'liquid tobe evaporated is'u'sually conducted as a.

film or layer traveling over or through heated tubes, as the case may be. 111 traveling through a heated tube, it is necessary to provide special means for an even annular distribution of the liquid upon the inner walls of the tube, and since most of these evaporators use a plurality of parallel tubes heated by a common steam acket and having a common feed. it is necessary to provide I special means whereby the distribution of the liquid to theseveral tubes shall be made uniform, so that each such tube shall receive substantially the same amount of liquid as every other tube.

In one of the modern types of evaporator known as the climbing film or Kestner type, the liquid is caused to travel upward as an annular film through a heated tube or series of tubes, into a sin-mounting separating chamber wherein the evaporated liquid is sep a-' rated from the vapor produced in evaporation. This chamber is usually under relatively low pressure, being connected with means for removing vapor and for producing more or less of a vacuum therein. It is caused to travel upward inthis manner by thepresence of a central bodyor core of steam or Vapor passing upward in contact with it inches. This chamber,

are apt and with considerable velocity: As actually manufactured, in this Kestner type of apparatus, there is a plurality of parallel vertical tubes surrounded by a commonsteam jacket. At. their lower ends, these tubes pass through a horizontal tube sheet into a feed'chamber, the ends of the tubes depending into this feed chamber forsome distance, say. several although. under greater pressure than that of the surmounting separating chamber and being a pressure chamberrelatively thereto, is usually Specification of Letters Patent. i F PatentedIDec. 26, 1911.

under less pressure than the source of sup-'- ply of the liquid. It operates under a pressure less than corresponds to the temperature of the liquid supplied to it. Into this chamber is led liquid. This liquid when coming from a relatively hot, or When'coining from a special preheater, on entering the feed chamber, undergoes self-evaporation, some .or much of its water flashing into vapor, T he vapor andliquid pass upward through the heated tubes, the liquid traveling upon the inner wall of the tube as an annular layer,.while the-vapor passes through the center ofthis annulus, In order to secure an even distribution of the liquid and vapor among the several. tubes and to insure each tube secur- 1 ing the same relative amounts of liquidand of vapor, the depending ends of the tubes are provided with laterally presented oriprevious eitect and therefore fices the lower ends being slotted or beveled as the case may be. The hot liquid-entering the feed chamber separates into vapor and liquid,'the vapor layer overlying the liquid layer. The laterally presented orifice at the base of the tube prolongations taps both the liquid and the vapor layers, insuring that some ofeach' shall enter each tube.' VVithout some such arrangement as this. the tubes to receive liquid and vapor alternately, or some of the'tubes may receive more liquid than others; someof the tubes may indeed be dry, taking nothing but verpor, while other tubes may be substantially or entirely filled'with liquid.

level of the liquid in such a feed chamber v v This is unde- .sirabl'e. It is, however, somewhat difficult the multiple effect is working under. differ ential pressure and the entering liquid comes into the effect under relatively high pressure, it enters the feed chamber with consid'able velocity and tends to bank up more or less at one point or another within such chamber. It may, for instance, if the inlet be somewhat tangential, pass around to the opposite side of the chamber and there bank up, giving a height of liquid higher than that next the inlet. Or the liquid may bank up near the inlet when coming in under less force. a

In the present invention, I have devised a process of and means for securing the desired even feed of both liquid and vapor to the several tubes and for insuring that each such tube shall .receive the same relative amounts'cf liquidand vapor as each other tube. For this purpose, I produce a preliminary separation of vapor and of liquid in a special prellminary chamber and then feed the vapor separated and the liquid separated individually into the feed chamber proper of the apparatus. And in the modification of my invention at present preferred, I'further introduce thesteam or vapor into each tube as a positive jet, drawing in the liquid after it by what may be termed an injector action. Where this is done, the

- prolongation of the tubes into port-ions depending into the feed chamber may be I omitted, as may the laterally presented orifices. vapor is effected in a preliminary chamber, it .is, of course, practically immaterial whether the liquid banks up more. at one point in such a chamber than at another,.

while the liquid separated may be fed uniformly from such chamber into the feed elf-amber proper.

While this invention in some of its aspects is applicable to any type of evaporator wherein an annular traveling layer of liquid is produced on the interior of a heated tube, in its present specific embodimentI regard it aslnore particularly applicable to evaporators of the stated Kestner or climbing film'type.

In the accompanying showing, I have shown more or less diagrammatically certain organizations of apparatus elements within the limits of the present invention and useful in the performance of the stated process. In this showing: Figure 1, isa

- sectional elevation of one form of apparatus embodying my invention; Fig. 2, is a sectional plan view of the same; Fig. 3, is}

a view similar to Fig. 1:, of a modified construction embodying my invention, and Fig. 4, is a sectional plan view of the structure shown in Fig. 3. a

In the operation of the elongated vertical tube evaporators of the said Kestner type in which evaporation is effected by film Wherethe separation of liquid and climbing of the liquid or liquid body under treatment, the essential result to be obtained is, as stated, the feeding of said liquid or liquid body to all of the tubes simultaneously and uniformly. The liquid coming from a previous evaporator is superheated; that is, it is higher in temperature than the boiling point of the evaporator in which it is introduced, and the result is that the instant the liquid passes the feed valve, the

pressure being reduced, the boiling point is reduced also and some of the liquid flashes intosteam, causing the liquid to be filled with bubbles.

In multiple effect evaparators, whether working under vacuo or under pressure, the relative pressure in each succeeding elfect is always lower than in the next preceding ;'effect and, concomitantly, the boilingpoint of the liquid passing successively through the several effects is also lowered so that the vaporsfrom the preceding effect shall always be hot enough to boil the liquid in the next succeeding effect. The liquid in passing from one effect'into the lower pressure of the next becomes partly vaporized and is full of bubbles of released steam. It 1 is very desirable that these bubbles of steam should be separated and separately introduced into the tubes for ascentand evaporation therein. One reason for this is that it is desirable to have a uniform liquid level near the ends of the tubes so that the feed in each tube will be uniform; the steam entering the tube independently of the liquid, at the top of a laterally presented orifice or slot when such arrangement is provided, and the liquid entering the slot therebelow and passing up the tube adjacent the walls of the same. If this level is not made uniform, or if there is a disturbance caused by the liquid entering at one side of the feed chamber, it will be readily understood that some of the tubes are apt to receive more liquidthan others;-

a condition that would interfere with the efficiency of the apparatus. presence of the large amount of vapor, due to'a fall in temperature and pressure when the liquid is passed from one efiect to the feed chamber of the next effect, there is always an opportunity for some of the tubes to receive a greater amount of liquid than others; and the essential object of mv invention is to provide means whereby the Owing to the ing 1 is a tube sage- 10 with an inlet conduit 11 through and flows via a passage ber 4 into which the pro ect and strikes a or vapor accompanying veloped within said chamber 7 circulates around the upper plish this, a separate chamber is provideddisposed adjacent the feed chamber which is indirect communication with the tubes, and provision 'is made for independenttransfer ,5 of the liquid and the steam or vapor to said 10 difficulties heretofore met with in feeding 1 liquid or liquid bodies undergoing treatment to the base of evaporating tubes In Figs. 1 and 2, of the drawings herewith, 1 represents the lower portion of a 1 heating shell; or casing shown as of the climbing film type and containingevapo rating tubes 2 to hich the liquid or liquld ..body to be concentrated is to be fed for therein. Carried by theshell or cassheet 3 to which the tubes are connected, while in the structure shown in Figs. 3 and 4, the tubes pass through said tube sheet into a feed chamber 4,and in ascent such; instance the tubes may be beveled or 25 provided with laterally presented orifices or slots 5, in the manner indicated in my prlor Patent No. 882,322.

Referring again to Figs. 1 and 2, 7. represents achamber disposed adjacent theca's- 30 ing 1, and into which the heated liquid to be'concentrated is fed from a suitable inlet 8, and in which chamber more or less per fect separation of the steam or vapor from the liquid maybe effected; such steam or- 35 vapor being passed directly to the evaporating tubes 2. For this purpose the chamber. 7 has a passage 9 fo'rdelivering the liquid to the chamber 4 below the tubes and in direct communication therewith, and a pasat the top of the chamber 7, which'passage communicates with a chamber 12 below said chamber 4, and from this chamber 12 the steam or vapor may enterfthe evaporating tubes 2- short sections of tubing indicated at 13. In this" form, of the structure, no

provisionis made for extending the tubes 2 -1nto the feed chamber,'but such arrangement is not thought to be necess'ary'with 50 this particular structure in view of the dil'ectmeans used for transferringthe steam or vapor to the evaporating tubes. 4.

In the structures shown in Figs. 3 and 4, the liquid enters an auxiliary chamber 7 14 to the feed chamevaporating tubes 2 deflector or battle 15 therein which serves to spread the liquid to allparts of said chamber. The steam the liquid or detop of the same and enters the feed chamber 4via a passage 16 which leads from a point near the top of said chamber 7 and portion of the shown comprising means ment it be used,

rises to the feed chamber try of the liquid therebelow and -with the latter wetting the inner walls of the tubes 2 uniformly and simultaneously; it facilitates the flow of liquid therein, and the operation in the subsequent concentration of the same.- With the projecting tubes, the laterally presented orifices 5 will t both steam and liquid layers, allowing a simultaneous entry of both into each tube, but with the structure of Fig. 1, positive means are provided for the delivery of liquid and of vapor into each evaporating tube and the beveling or 4 simultaneously with the'enslotting of the tube ends and their prolongation becomes unnecessary.

-The structures shown herein as auxiliary to the evaporator may be of sheet metal or cast metal, or parts may be of sheet metal and parts of cast metal. The tubes 2 may be projected into the feed chamber 4 as indicated in the structure 4, to any desired extent; the desirability of such extension depending in some measure upon the size and capacity of the evaporating element. The several feed chambers shown in Figs. 3 and.

are provided with suitable drainage out-lets l8 closed by plugsor other suitable devices, or they may be provided with valves 20. In addition, the feed 'chamber ineach instance is so constructed and arranged and of such size with respect to the shell containing the evaporating tubes that all of said tubes are accessible when said feed chamber or the lower portion of the same is removed. I

The feature of the present invention is the provision of auxiliary means exterior of the main feed chamber and in communication with the evaporating tubes for the sepa-,

ration of the steam or vapor from the liquid, and the separate feeding of said steamor vapor and of said liquid to the tubes.

An evaporator with the auxiliary devices for effecting an even feed' and distribution of the liquid may be used as a single evaporating effect or as any effect of amultiple'efi'ect system and it may be operated under a pressure greater or less thanthat of the atmosphere.-

Any number of similar effects of this type may be arranged in a multiple efi'ectsystem or one such effect may be arranged in combination with effects of a different type. It should, however fin whatever arrangebe so arranged as to receive a supply of liquid of a heat greater than the boiling pointat the pressure prevailing in the effect so as to permit self evaporation to take place in the preliminary chamber. When used as a single effect or as the first efiect of a multiple, fore be coupled with a source of preheated liquid.

Iclaim: v

' 1. In an evaporating apparatus, an evapit should thereorating tube, a heating casing surrounding such tube, a source of heated liquid, an expansion chamber receiving such heated liquid, a vapor conduit leading from such chamber "and in communication with such tube, and a liquid conduit leading from such chamber and also in communication with such tube.

2. In an evaporating apparatus, a vertie cal evaporating tube, a heating ca'slng surrounding such tube, a source of heated liquid, an expansion chamberreceiving such heated liquid, a vapor conduit leading from such chamber and in communication with such tube, and a liquid conduit leading from such chamber and also in communication with such tube.

3. In an evaporating apparatus, an evaporating tube, a heating casing surrounding such tube, a source ofheated liquid, an ex- .pansion chamber receiving such heated heated liquid, a vapor conduit leading from such chamber and having a prolongation eX- tending some dlstance within the end of such evaporating tube, and a liquid conduit leading from such chamber and also in com-- munication with such tube.

5. In a tubular evaporator, the combina-' tion of a feed chamber at the base of the tubes for receiving heated liquid under treatment, evaporating tubes leading upwardly from said. chamber, a chamber situated independently of said feed chamberfor initial reception of the liquid to permit separation of'vapor therefrom, and means for the separate delivery of liquid and vapor to the evaporating tubes. J I

6. Inan evaporating apparatus, the combination of vertical tubes, a feed chambercommunicating with the lower ends of the same, a chamber for the reception of heated liquid-undergoing treatment in which accompanying vapor may separate from such liquid, and means for separately passing Vapor and liquid to the evaporating tubes.

7 In an evaporating apparatus, the combination of vertical tubes, a chamber commucating withthe lower ends of the same, a

' chamber, for the initial reception of heated liquid undergoing treatment in which accompanying vapor may separate from suchli'quid, a plurality of chambers below the lower ends of the tubes, one of which communicates directly ,with said tubes, and separate passages for vapor andliqu'id leading from the separating chamber to the chambers below. the ends" of the tubes, one of said chambers having vapor outlets communicating with the evaporating tubes. Y

8. The combination of an evaporator having vertical heating tubes in an inclosing casing, means at the base of said casing for feeding liquid and vapor into said tubes, a releasing casing having an inlet for liquid to be treated, a conduit establishing communication between the upper part of said re-' leasing casing, and said feed means, and another conduit establishing communication between the lower part of said releasing casing and said feed means.

9. The combination of an evaporator having vertical heating tubes in an inclosing,

casing, means at the base of said casing for feeding liquid and vapor into said tubes, a releasing casing having an inlet for liquid to be treated, a conduit establishing communication between the upper part of said releasing casing and said feed means, said conduit having an extension within the base of each evaporating tube, and another conduit establishing communication between the lower part of said releasing casing and said feed means.

10. The combination of an evaporator, means for evaporating liquid as a climbing film, feeding means, a source of heated liquld, means for permittlng a release of vapor ,fromsuch liquid, and means for separately conducting the released vapor and the residual liquid to said feeding means. I

11. An evaporating element having a pressure chamber and" vertical tubes extending into said chamber, in combination with means for separating vapor from liquid and delivering it to said pressure chamber above the inlets to said tubes, and means for con- 've in li uid from which said vapor is separated to said pressure chamber below the inlets to said tubes.

12. The combination of a' vertical tube evaporator, means for relieving the pressure on a body of heated liquid to form separate bodies of vapor'and liquid, means for delivering the residual liquid to the lower ends of the tubes and means for delivering vapor to the tubes to facilitate the passage of the liquid into and through the same. 13. The combination of a vertical tube evaporator, means for causing self evaporation ina body of liquid to be treated, means for delivering the residual hot-liquid to the bottoms of the evaporator tubes and means for supplying a jet of vaporto the bottoms of the tubes to facilitate the flow I of said liquid into and through the same.

14. The combination of a vertical tube evaporator having a feed chamber at the lower' ends of the tubes, a container for re lieving thepressure on a body of liquid to be treated to permit self evaporation thereof, a

conduit for delivering the residual liquid name to this specification, in the presence of freim said container to t1e fged chambier, two subscribing Witnesses. an means inc ependent 0 sai conduit or delivering vapor to the feed chamber to fa- PAUL KESTNER' cilitate the passage of the liquidinto and 1 \Vitnesses:

through the tubes. 4 HENRI CHARRIER, In testimony whereof, I ha-ve signed my LI'KJN PEOKEL. 

